This application claims priority to British Application No. GB 9929355.7 filed Dec. 10, 1999.
The present invention relates to the field of alarm and warning systems and, in particular, to a system which detects activity and controls buzzers, lights, etc.
Common types of burglar alarm systems and other warning devices have a detector, which is activated by the presence of a moving object, and a buzzer or ringer, which is designed to alert the public in response to the detector activating. Often, such systems also have lights which flash on or off and/or move in response to the detector activating. These systems are typically complex and difficult to operate, they are designed to activate warning devices continually or at regular intervals which can cause a nuisance, and the sensors thereof are designed to be in full view, which means a person approaching the system may see the system and avoid detection, or otherwise, deactivate the warning device if it has already been activated. Such systems are, in general, unsuitable for discretely warning others that a person has been detected.
U.S. Pat. No. 4,755,792 discloses a security system for detecting an intrusion and has a controller and slave modules which operate electrical appliances connected thereto. The systems operates the electrical appliances in response to activation of entry detectors after a time delay which allows the system to be disarmed before the appliances are activated.
U.S. Pat. No. 5,650,773 discloses a intrusion warning system in which a control unit is used to operate electrical devices, such as lights, in response to an occurrence detector activating. The period of operation of the electrical devices or the delay in the operation is set by a timer which delays the arming or rearming of the control unit.
There is a need to provide a warning system which is simple and easy to operate, and which, if necessary, can be simply adapted by the user so that it warns the user of the presence of a person in the vicinity of the system in a discreet manner and helps confuse intruders.
According to one aspect, the present invention consists in a warning system including a controller and one or more inputs and one or more outputs, the input(s) comprising one or more activity sensors and the output(s) comprising one or more lights, and in which the controller is adapted to operate the one or more lights after a time delay in response to the activation of the activity sensor or one of the activity sensors and the controller is adapted to extend the period of operation of the light(s) in response to one or more further activations of the activity sensor or one of the activity sensors during operation of the light(s). The delay may be adjusted and is not less than say 5 seconds.
According to another aspect, the present invention consists in a method of operating a warning system having a controller and one or more inputs and one or more outputs, the input(s) comprising one or more activity sensors and the output(s) comprising one or more lights, including the steps of activating the activity sensor or one of the activity sensors when the presence of a moving body is detected, operating the light(s) after a time delay in response thereto, further activating the activity sensor or one of the activity sensors when the presence of a moving body is detected during operation of the light(s), and extending the period of operation of the light(s) in response to the or each further activation of the activity sensor or one of the activity sensors.
Preferably, the warning system includes a light sensor and a first buzzer, and the controller is adapted to operate the first buzzer in response to the activation of the activity sensor and operate the first buzzer and the light in response to the activation of the activity sensor when the light sensor is in an activated state. Preferably, the light is activated after a significant time delay which can be adjusted.
The warning system may include one or more first and second buzzers, light sensors and controllers. The or each controller is adapted to operate the first buzzer(s) in response to the activation of the activity sensor(s), and operate the first and second buzzers and the light(s) in response to the activation of the activity sensor(s) when the or each light sensor is in an activated state.
The warning system may be installed in a house or similar structure. Several sensors may be connected in parallel in order to sense a moving object within the perimeter of a property. Different controllers may be used in order to sound the same or different buzzers and/or switch the same or different lights in response to different activity sensors being activated. Several lights may be connected in parallel including the light in a room of the house in order to give the impression that an occupant of the house has awoken in response to the activity sensor(s) activating. The warning system may also comprise video equipment which the controller activates in response to the activity sensor(s) activating. Mechanical switches may be included in the warning system to enable the light(s) and/or buzzers(s) to be activated manually.
Preferably, when the warning system includes a first buzzer and a light sensor, the method of operating the warning system includes the steps of the controller operating the first buzzer in response to the activation of the activity sensor, the controller operating the first buzzer and the light in response to the activation of the activity sensor when the light sensor is in an activated state. Preferably, the method includes operating the light after a significant time delay which can be adjusted and which is not less than say 5 seconds.
When the warning system includes a second buzzer, the method of operating a warning system includes the steps of the activity sensor activating when the presence of a moving body is detected, the controller operating the first buzzer in response to the sensor activating, and the controller operating the light and the first and second buzzers in response to the activity sensor activating when the light sensor is in the activated state.
Preferably, the controller may be adapted to switch on the first buzzer for a first pre-set time period and may be adapted to delay switching on the light for a second pre-set time period. Furthermore, the controller may be adapted to switch on the light for a third pre-set time period. The light sensor may be in an activated state in darkness and in a deactivated state in daylight, or alternatively, in an activated state in daylight and a deactivated state in darkness. The controller may be adapted so that any of the first, second, third or fourth pre-set time periods are manually adjustable. Typically, the controller may be adapted so that the first buzzer and/or the second buzzer and/or the light can be manually switched to operate independently of the controller. The first buzzer may be an electric doorbell of a house.
According to a feature of the present invention, the controller is adapted to switch on the second buzzer for the first pre-set time period when the first pre-set time period is the same or shorter than the second pre-set time period and is adapted to switch on the second buzzer for the second pre-set time period when the first pre-set time period is the same or longer than the second pre-set time period.
According to another feature of the present invention, the controller is adapted to extend the third pre-set time period in response to the combined activation of the activity sensor and light sensor whilst the light is switched on.
According to yet another feature of the present invention, the controller is adapted to prevent further switching on the first buzzer for a fourth pre-set time period once the controller has switched on the first buzzer.
According to yet another feature of the present invention, the method of operating the present invention may also include any of the following steps: the controller switching on the first buzzer for a first pre-set time period; the controller switching on the light after a second pre-set time period; the controller switching on the light for a third pre-set time period; the controller switching off the second buzzer after the first pre-set time period when the first pre-set time period is the same or shorter than the second pre-set time period and the controller switching off the second buzzer after the second pre-set time period when the first pre-set time period is the same or longer than the second pre-set time period; the controller extending the third pre-set time period each time the activity sensor is activated whilst the light sensor is in the activation state and the light is switched on; the controller preventing the first buzzer from further switching on for a fourth pre-set period once the controller has switched on the first buzzer; the controller disconnecting the buzzer circuitry from the activity sensor(s) for the duration of forth present time period; the controller disconnecting the first buzzer and/or the second buzzer and/or the light from the controller.
Some major advantages of the present invention are that it is simple and easy to use and the delayed action of the light switching on helps conceal the activity sensor and confuse intruders. Extending the time period for which the light remains on if a person is further detected permits simple tasks to be performed at night without having to manually switch the light on. The present invention allows the warning system to be flexible in its installation, configuration and testing; it may not require resetting in the event of a power failure; and it may be easily configured to operate as a conventional alarm system or, as a warning system which discreetly warns the user that a person has been detected. An advantage of a feature of the present invention is that the light and second buzzer are only switched on by the controller in darkness or when ambient light intensity is below a predetermined threshold and not during daylight when they are likely to cause a nuisance. The discreet buzzer may notify the occupant of the house immediately a person enters the house without alerting the person to the fact that they have been detected. The second buzzer can be situated in a bedroom so as to ensure the occupant is alerted at night and/or that other occupants in other rooms are not disturbed.